氮化硼與石墨烯有著相似的結構並有鋸齒型(zigzag)與扶手椅型(armchair)兩種邊緣結構，具有獨特的物理與化學性質，是一種優良的熱學材料。雖然氮化硼的熱傳導係數低於石墨烯，但卻遠超其他金屬和非金屬材料，由氮化硼與石墨烯相結合的熱電元件受到了越多的關注。
本研究主要以非平衡態分子動力學模擬方法，探討氮化硼奈米帶在尺度效應、溫度效應、空位缺陷效應、同位素摻雜效應下其熱傳導係數的變化，並以聲子狀態密度分析材料聲子內部碰撞情形，了解在上述效應下其熱傳導係數下降之原因。
一般而言，氮化硼奈米帶製造過程中，其反應腔室不可避免的會含有微奈米級的顆粒或灰塵，導致其內部產生缺陷，故本文為了模擬此上述情況，建立具有缺陷的氮化硼奈米帶，來更接近現實中的氮化硼奈米帶，提供不同缺陷率以及在溫度效應下的熱傳導係數參考值。
此外在自然狀態下，氮化硼並不是以純氮化硼而是以同位素的形式存在的，其中以19.9 %的11B以及15N最為常見，故本文為了模擬此上述情況，建立具有同位素摻雜的氮化硼奈米帶，來更接近現實中的氮化硼奈米帶，以提供11B、15N 不同摻雜率以及在溫度效應下的熱傳導係數參考值。
最後，發現在各種效應下鋸齒型氮化硼奈米帶的傳熱表現都比扶手椅型來的好，因此鋸齒型為氮化硼奈米帶之最佳熱學材料。

Boron nitride has a similar structure to graphene, both having two edge structures, zigzag and armchair. It has unique physical and chemical properties and is an excellent thermal material. Although the thermal conductivity of boron nitride is lower than that of graphene, it is much higher than other metals and non-metallic materials. Thermoelectric components consisting of boron nitride and graphene received more and more attention.
In this study, the non-equilibrium molecular dynamics simulation method is mainly used to investigate the changes of thermal conductivity of boron nitride nanoribbons under scale effect, temperature effect, defect effect, and isotopic doping effect. Using the phonon density of state to analyze the internal collision of phonons helps us understand the reasons for the decrease of thermal conductivity under the above effects.
Generally speaking, in the manufacturing process of boron nitride nanoribbons, the reaction chamber inevitably contains micro/nano-scale particles or dust, which causes defects in its interior. Therefore, in order to simulate the above situation, this study creates a model with the defects. This model provides reference values of thermal conductivity under different defect rates and temperature effects.
In addition, in the natural state, boron nitride does not exist as pure boron nitride but in the form of isotopes, among which 19.9% 11B and 15N are the most common. Therefore, to simulate the above situation, this paper establishes the isotope-doped boron nitride nanoribbons. This provides the reference values of thermal conductivity under different 11B, 15N doping rates and temperature effects.
Finally, it is found that the heat transfer performance of the zigzag boron nitride nanoribbons is better than that of the armchair type under various effects, so the zigzag-type is the best type of boron nitride nanoribbons in this paper.

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